Fuel injectors are routinely housed in the fuel injector bore of a cylinder head that is configured to closely match the outside shape of the fuel injector. Seals are disposed at one or more places between the outside housing of the fuel injector and the inside surface of the fuel injector bore of the cylinder to prevent the leakage of fuel into the water jacket of the cylinder head. Over time, the areas located adjacent the seals on the inside surface of the fuel injector bore may become worn or pitted, which may reduce the effectiveness of the seals to prevent leakage of the fuel into the water jacket. More particularly, fuel may seep into the areas between the fuel injector and the surfaces of the bore of the cylinder head, which along with heat, may produce pitting of the surfaces because of the corrosive nature of the sulfur in the fuel catalyzed by the heat, negatively impacting the effectiveness of seal in that area. Eventually, a leak may occur and this may lead to the engine malfunctioning, necessitating repair and maintenance and an associated economic loss for the industrial endeavor using the engine.
Of course, it may be difficult and/or expensive to repair or replace the cylinder head. One known method for repairing threaded components is disclosed by U.S. Pat. No. 8,601,663 to Ngo et al. As shown by the abstract of Ngo, this patent is directed to repairing damage to an internally threaded opening. More specifically, methods are provided for structurally repairing a component having a damaged internally threaded opening. The damaged internally threaded opening is machined to a predetermined diameter, thereby forming a machined opening. At least one notch is formed in the machined opening, thereby forming a notched opening. A selected amount of repair material is cold sprayed into the notched opening, including into the at least one notch. A plurality of internal threads is formed from the repair material to form a repaired internally threaded opening in the component. The repaired components are also provided. However, this process does not teach how to provide a suitable repair so that a fluid tight seal may be provided and maintained in a harsh environment such as an engine where temperatures and corrosive agents may be present.
Accordingly, it is desirable to develop a method and apparatus that may allow the user of an engine to remanufacture, refurbish or otherwise repair the fuel injector bore of a cylinder head that may house a fuel injector and provide a fluid tight seal between the fuel injector and the cylinder head in a reliable and economic manner.